These cases are always trying, but it is very rarely necessary to resort to embryotomy. When absolutely required, first remove one fore limb, and then, if still unsuccessful, the other, after which the head can easily be secured. (See "Embryotomy," p. 202.) _Head turned upward and backward._--In this case the face rests upon the spine; the forefeet appear alone in the passage, but fail to advance, and on examination the rounded, inferior border of the neck can be felt, extending upward and backward beneath the spine of the dam, and if the calf is not too large the hand may reach the lower jaw or even the muzzle. (Pl. XVI, fig. 5.) A repeller is planted in the breast and the body of the calf pushed backward and downward so as to make room and bring the head nearer to the passage; or in some cases the body may be pushed back sufficiently by the use of the fore limbs alone. Meanwhile the head is seized by the ear or the eye socket, or, if it can be reached, by the lower jaw, and pulled downward into position as space is obtained for it. If the hand alone is insufficient, the blunt hooks may be inserted in the orbits or in the angle of the mouth, or a noose may be placed on the lower paw, and by traction the head will be easily advanced. In case of a large fetus, the head of which is beyond reach, even when traction is made on the limbs, a rope may be passed around the neck and pulled, while the breastbone is pressed downward and backward by the repeller, and soon the change of position will bring the orbit or lower jaw within reach. With the above-described position the standing position is most favorable for success, but if the calf is placed with its back down toward the udder, and if the head is bent down under the brim of the pelvis, the best position for the cow is on her back, with her head downhill. In neglected cases, with death and putrefaction of the fetus and dryness of the passages, it may be necessary to extract in pieces. (See "Embryotomy," p. 202.)